Gas cap ?

Radar

Took the 1987 Monte Carlo SS out for a spin last night and it started running a little rough so i called my mech. today to see if he could look at it and he said to add some heat to the gas. I just filled it a few days ago and he was thinking i maybe got a little water,so when i took off the gas cap i could hear a lot of pressure release.Is that normal ?

Gun_Poor

How does it run now?

Radar

It is running ok but it still gets pressure in the tank after a short drive. quote:Originally posted by Gun_Poor
How does it run now?

nmyers

Normal. Gasoline vapors are now recycled, rather than just vented; reduces pollution.

A crack in the gas cap flange can cause rough idling, & will cause you to fail emission tests. Cheap enough to replace the gas cap.

Neal

select-fire

Normal

Brookwood

A bad fitting gas cap will cause the engine light to come on in your dash board.

spasmcreek

yours has in tank pump..maybe it is going bad running more than it should ????

savage170

not certain when GM changed their fuel system but some of the early 80's cars had a purge valve that would go bad letting it build excessive pressure and making it run rich and fouling the plugs

bs233jl

I had a 1987 Monte Carlo. Loved it. It looked fast just sitting still. Got it for $900 in 1998. Drove it 2 years, gave it to my son. Told him don't mess with it and it will be great transportation. 2 weeks later he puts in a chip to make it go "Faster". What a ding-dong...[:)]

grumpygy

Find this thing and replace it Purge Valve.